If some T3 is needed, it's easier to regulate by adding some T3 as a separate pill. Also, if on Armour
, be sure to have your free T3 monitored regularly.
T4 is the therapy of choice for those just starting thyroid hormone replacement. If it doesn't work for you, you can always try something else.
The synthetic vs. natural issue can get quite heated at times. Both sides have their supporters and detracters.